不同时间脑室注射脑源性神经营养因子治疗新生大鼠缺氧缺血性脑损伤效果的比较

Effects of different interval intracerebroventricular administration of brain-derived neurotrophic factor on hypoxic ischemic encephalopathy in neonatal rats

目的 比较新生大鼠缺氧缺血性脑损伤后不同时间脑室注射脑源性神经营养因子 (BDNF)对脑损伤的影响。方法 7d龄SD大鼠左侧颈总动脉结扎后行 8%低氧吸入 2 5h形成缺氧缺血性脑损伤 ,伤后 0、1和 4h分别向脑室注射0 5 μgBDNF ,观察对脑水肿、皮层和海马脂质过氧化物(MDA)水平和细胞凋亡的影响。结果 伤后即刻给予BD NF减轻脑水肿、防止MDA过量产生和细胞凋亡增加的效果最为显著 ,伤后 4h给予效果较差。结论 BDNF对新生大鼠缺氧缺血性脑损伤后的皮层和海马具有显著的保护作用 。

AIM To observe the effects of different interval administration of exogenous brain derived neurotrophic factor (BDNF) on hypoxic ischemic encephalopathy in neonatal rats. METHODS BDNF (0 5 μg) was microinjected intracerebroventricularly at 0, 1 and 4 h after the hypoxic ischemic encephal opathy in 7 d neonatal Sprague Dawley rats undergone by ligation of left common carotid artery followed by a 2 5 h inhalation of humidified 8% O 2+92% N 2 at 37℃ immediately after the injury, respectively. Changes of brain edema, levels of malondialehyde (MDA) and neuronal apoptosis at the left cortex and hippocampus were investigated 24 h after the injury. RESULTS The most prominent effect of BDNF was seen in 0 h group with a marked decreases in brain edema and levels of MDA and a significantly alleviated neuronal apoptosis while it was lowered obviously when administered at 4 h after the insult. CONCLUSION BDNF exerts a prominent protective effect on hypoxic ischemic encephalopathy in neonatal rats when given as early as possible after the injury rather than later administration.